| 摘要 |
FIELD: noble metal chemistry. ^ SUBSTANCE: metal platinum is dissolved in chloronitric acid at elevated temperature to provide solution of platinum hydrochloric acid. Metal platinum is used in powder form with particle size of 30-150 mum. Dissolution is carried out under agitation at initial speed of 30-150 rpm and temperature of 60-650C. Further agitation speed is raised up to 300-400 rpm and temperature is raised up to 80-900C. Further agitation is carried out at speed of 50-60 rpm and temperature of 55-65 0C. Produced solution is concentrated in vacuum evaporator at 45-550C and residual pressure of 0.1-0.2 atm. Direct yield of metal platinum from powder is 99.2-99.3 %. Duration of dissolution process is 3.5-4.0 h. ^ EFFECT: high platinum yield and reduced nitric oxide exhaust. ^ 2 cl, 2 ex |
